Thomas G, Selak M, Henson P M
Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraíba, João Pessoa, PB, Brazil.
Phytother Res. 1999 Feb;13(1):9-13. doi: 10.1002/(SICI)1099-1573(199902)13:1<9::AID-PTR389>3.0.CO;2-E.
An aqueous fraction (10-300 micrograms/mL) of the ethanol extract of the leaves of Cissampelos sympodialis Eichl inhibited N-formyl-Met-Leu-Phe (fMLP)-induced release of lysozyme and myeloperoxidase from human neutrophils. Inhibition by the fraction, as well as by dibutyryl-cAMP and prostaglandin E2, was substantially greater when the cells were pretreated with the phosphodiesterase (PDE) inhibitor isobutyl methyl xanthine (IBMX) indicating that the effect may be mediated by cAMP. Measurement of intracellular cAMP levels showed that the fraction (30-100 micrograms/mL) increased the nucleotide levels in IBMX-pretreated neutrophils which was unaffected by propranolol. Cyclic AMP dependent protein kinase A activity was also increased by the fraction (1.5-100 micrograms/mL). Superoxide anion generation induced by fMLP in cytochalasin B-treated cells primed with PAF was not inhibited by the aqueous fraction. The results indicate that the aqueous fraction of Cissampelos sympodialis inhibits neutrophil degranulation by a cAMP-dependent mechanism which may be relevant to the use of the plant as an anti-asthmatic agent in folk medicine.
串珠锡生藤（Cissampelos sympodialis Eichl）叶乙醇提取物的水相部分（10 - 300微克/毫升）可抑制N-甲酰甲硫氨酰-亮氨酰-苯丙氨酸（fMLP）诱导的人中性粒细胞释放溶菌酶和髓过氧化物酶。当细胞用磷酸二酯酶（PDE）抑制剂异丁基甲基黄嘌呤（IBMX）预处理时，该部分以及二丁酰环磷腺苷（dibutyryl-cAMP）和前列腺素E2的抑制作用显著增强，这表明该效应可能由环磷腺苷（cAMP）介导。细胞内cAMP水平的测定表明，该部分（30 - 100微克/毫升）可增加经IBMX预处理的中性粒细胞中的核苷酸水平，而普萘洛尔对此无影响。该部分（1.5 - 100微克/毫升）还可增加环磷腺苷依赖性蛋白激酶A的活性。在经血小板活化因子（PAF）预处理并用细胞松弛素B处理的细胞中，fMLP诱导的超氧阴离子生成不受该水相部分的抑制。结果表明，串珠锡生藤的水相部分通过一种cAMP依赖性机制抑制中性粒细胞脱颗粒，这可能与该植物在民间医学中作为抗哮喘药物的用途有关。
